A NEW PHYTOSEIID (ACARINA: MESOSTIGMATA) FROM APPLE IN NOVA SCOTIA

1970 ◽  
Vol 102 (8) ◽  
pp. 1022-1024 ◽  
Author(s):  
H. B. Specht ◽  
Aly H. Rasmy

AbstractThe female of Amblyseius duncansoni n. sp., is described and illustrated. It was taken in Nova Scotia from the bark of dormant apple trees in early winter and prior to bud burst.

2015 ◽  
Vol 68 ◽  
pp. 250-256 ◽  
Author(s):  
N.T. Amponsah ◽  
M. Walter R.M. Beresford ◽  
R.W.A. Scheper

Leaf scar wounds are important sites for Neonectria ditissima infection of apple trees Monitoring leaf fall in Scilate/Envy and Braeburn trees to estimate leaf scar wound presence showed maximum leaf scar incidence occurred in June (early winter) Wounds detected in New Zealand apple orchards were bud scale scars fruit thinning and picking wounds leaf scars and pruning cuts Picking wounds are caused during harvest where the pedicel is detached from the shoot Susceptibility of these different types of wounds was determined using artificial inoculation of N ditissima conidia during the season Pruning cut wounds were the most susceptible followed by fruit picking and thinning wounds and the least susceptible were leaf scar wounds No infections were observed when bud scale wounds were inoculated There was no difference in wound susceptibility between cultivars but overall Scilate/Envy wounds developed more lesions than Braeburn wounds


1965 ◽  
Vol 97 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
H. J. Herbert

AbstractIn Nova Scotia one leaf cluster with an adjoining 1 inch of twig taken from the inside of each of 10 apple trees replicated four times is an adequate sample unit to measure the density of the brown mite.The brown mite has one generation with a partial second in some orchards and one with a partial second and partial third in others. The first generation adults in the bivoltine and trivoltine populations lay summer eggs on the leaves and twigs, and diapause eggs on tin twigs. The second generation adults in the bivoltine populations lay only diapause eggs; in the trivoltine populations they lay both summer and diapause eggs. The adults of the third generation lay only diapause eggs.The brown mite is found on both the leaves and woody parts of the tree. In orchards with bivoltine populations the proportion of mites on leaves reached a peak of 80% by mid-July, but thereafter gradually decreased to 10% by the end of August. However, in orchards with trivoltine populations the proportion of mites on leaves reached a peak of 80 to 90% by mid-July, remained constant until mid-August, and thereafter decreased to approximately 40% by the end of August.The number of diapause eggs laid by adults of each generation in both the bivoltine and trivoltine populations varies widely. The eggs are deposited on the trunk as well as on the branches, with the heaviest deposition in the central area of the tree. The diapause eggs laid by adults of the first generation are the last to hatch and those laid by the third generation are the first to hatch the following spring.The factors responsible for the differences in the number of generations and in the number of diapause eggs laid are unknown.


2007 ◽  
Vol 121 (1) ◽  
pp. 76 ◽  
Author(s):  
David J. Garbary ◽  
Barry R. Taylor

Over 85 records of 23 species of blooming, herbaceous angiosperms were made at 19 sites in Antigonish County between 7 and 21 January 2006, when daytime temperatures reached 15°C. These observations followed an unusually warm fall and early winter. All species were observed on waste ground or in fields and garden plots, except for Epigaea repens L. which was part of ground vegetation in a sparsely wooded site. The primary families represented were Asteraceae (six species), Brassicaceae (six species) and Carophyllaceae (four species). The most commonly observed plants were Taraxacum officinale (L.) Weber (11 sites), Capsella bursa-pastoris (L.) Medik. (nine sites), Thlaspi arvense L. (three sites) and Stellaria media (L.) Vill. (four sites). Many plants and inflorescences were conspicuously frost-damaged, and flowers were rarely fully open. In several species, e.g., T. arvense and Cerastium vulgatum L., many individual plants looked normal and there was no evidence of frost damage. These observations are the latest flowering records for Nova Scotia.


1989 ◽  
Vol 67 (3) ◽  
pp. 552-558 ◽  
Author(s):  
I. A. McLaren ◽  
Estelle Laberge ◽  
C. J. Corkett ◽  
J.-M. Sévigny

The primarily arctic Pseudocalanus acuspes, relict in Bedford Basin, Nova Scotia, produces a first generation (G1) in late winter; most G1 individuals mature in late spring. The G1 then produces a G2, most of which "rest" in copepodite stages III and IV until early winter. These stages store large amounts of lipid in early summer, which slowly diminish subsequently. A small number of G2 individuals continue to develop at temperature-dependent rates, maturing in early autumn and producing G3 adults in November. Copepodites developing in winter and spring store less lipid. The primarily arctic Pseudocalanus minutus, rare in Bedford Basin and on the Scotia Shelf, is strictly annual, developing to a lipid-filled copepodite stage V after spawning in late winter. The arctic–temperate Pseudocalanus newmani is abundant on the Scotian Shelf, but may not be self-sustaining when advected into Bedford Basin. It stores little lipid and appears to have at least three mature generations at temperature-dependent intervals over Browns Bank between May and November. It may rest in winter, or its life-cycle synchrony by spring could result from food-limited development during winter. The temperate Pseudocalanus moultoni appears to have a life cycle similar to that of P. newmani, but was less common during summer on Browns Bank. These life cycles are appropriately adapted to the geographical ranges of the species, and show some parallels with species of Calanus.


1973 ◽  
Vol 105 (2) ◽  
pp. 271-276 ◽  
Author(s):  
H. J. Herbert ◽  
K. P. Butler

AbstractThe relative densities of phytophagous and predacious mites within mature apple trees were examined. The eggs of phytophagous mites Aculus schlechtendali (Nal.) and Panonychus ulmi (Koch) were more numerous in the lower position of the tree while the reverse was true for the predacious mite Zetzellia mali (Ewing) and its eggs.


1933 ◽  
Vol 8 (1) ◽  
pp. 433-458 ◽  
Author(s):  
R. A. McKENZIE

From 1925 to 1933 inclusive, during the summer season, 8,774 cod were tagged at eight points along the coasts of Nova Scotia and Prince Edward Island and eight per cent were recaptured during the following years, none after the sixth.Cod performing a restricted migration (less than 40 kilometres) were found to be in the majority off Halifax from July to September and off Shelburne in June and August in certain areas.Near Seal island in June, off Shelburne in July and September, and off Glace Bay in July and August, the majority of the cod were found to show orderly extended migrations. In the first two instances this movement was shoreward in the summer and seaward to about 130 metres in the early winter. The Glace Bay cod moved from the offshore banks just west of the Laurentian channel to the Cape Breton vicinity in the summer, returning early in the winter.A small percentage of the various stocks of cod performed roving migrations.The complete forsaking of the Cape Breton district for the offshore banks in the winter is attributed to the unfavourable ice cold water, while south-westward of Canso the movement off shore is thought to be caused by the very warm water inshore in the autumn and continued through the influence of the cold inshore waters several months later.As they grow older, the Shelburne cod remain progressively a little farther off shore when they move to shoal water each summer.


1962 ◽  
Vol 94 (9) ◽  
pp. 934-941 ◽  
Author(s):  
H. J. Herbert

Morgan and Anderson (1957) discussed in detail the synonymy of the Bryobia praetiosa Koch complex. They raised the apple inhabiting form to species status, and gave it the name, brown mite, Bryobia arborea.The brown mite from apple trees in Nova Scotia was examined by C. V. G. Morgan, Summerland, British Columbia, and found to be morphologically similar to the B. arborea on apple in British Columbia. It is possible, however, that the Nova Scotian form may be a geographical race.


1977 ◽  
Vol 109 (6) ◽  
pp. 797-806 ◽  
Author(s):  
C. R. MacLellan

AbstractThe population densities of several major apple pests and their natural enemies were studied in an insecticide-free young bearing orchard and in an older orchard of semidwarf trees on an integrated control program. In mature orchards of standard size trees, greater natural mortality occurs than that reported in this study. Over a 5-year period most pests, with notable exceptions, increased rapidly under insecticide-free conditions whereas occasional numerical surges of certain pest species occurred under the mild insecticide program. Insect damage on fruit at harvest averaged 24% in the insecticide-free orchard and 8% in the integrated control orchard which had 2.4 times more harvested fruit.


1965 ◽  
Vol 97 (3) ◽  
pp. 287-298 ◽  
Author(s):  
F. T. Lord

AbstractProblems associated with quantitative estimations of mixed populations of several species of predators on apple trees are discussed. The problems arise largely because of the inherently high variability in such populations and because of the mechanical difficulties of counting predators on some basic unit of tree. In this investigation two devices used in sampling are described and their efficiency rated. One, a vacuum sampler, that removed predators from samples of leaf clusters on the tree failed to meet the standards set. The other, called the shaker sampler, tumbled clusters about in a revolving wire screen cage to dislodge predators for counting. The amount of processing with this device to remove practically all predacious specimens was calibrated. When the shaker-sampler technique was applied to studies in two orchards it proved to be practical for quantitative estimation of predator populations per large limb. The error associated with estimations of the density of individual species was usually very high so that pooling of the results for several or all species was required to reduce the variance to an acceptable level.


1954 ◽  
Vol 86 (3) ◽  
pp. 128-135 ◽  
Author(s):  
A. W. MacPhee ◽  
K. H. Sanford

The toxicities of a large number of spray chemicals to arthropod pests are well known. In most instances, observations on the effects of such materials on natural enemies have beeen incidental to other studies, and little has been published on experiments designed to determine the direct toxicities of the chemicals to beneficial species. The effects of spray chemicals on the predators and parasites of the major pests of apple trees in Nova Scotia have been investigated as part of a broader project on the factors that influence population densities of orchard arthropods, as outlined by Pickett et al. (31).


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